Form for concrete floors



March 16 1926. 1,577,316

T. JAHNSEN FORM FOR CONCRETE FL'ooRs' Filed Sept. 29; 1922 v2 Sheets-Sheet 2' IN VEN TOR M1 ATTORNEYS Patented Mar. 16, 1926.

UNITED, STATES THORALF JAHNSEN, or JERSEY CITY, NEW :rnnsnY.

FORM ron cononn'rn rLo'ons.

Application filed September 29, 1922. Serial No. 591,214.

To all whom it may concern:

Be it knownthat I, TrioRALr' JAHNsnN, a citizen of the United States, residing at #2 Duncan Court,- Jersey City, in the county of Hudson, State of New Jersey, have invented certain new and useful Improvements in Forms for Concrete Floors; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The floors of reenforced concrete buildings are commonly supported by reenforced concrete columns. In order to strengthen the floor and the better to distribute the load, these supporting columns are usually provided with flaring conical capitals surrounded by wide square slabs or abacuses, all properly reen'torced. In constructing these, the parts are integrally cast, and column, capital, abacus and fioor are monolithic. In practice the column forms are set up on the foundation or supporting floor and the upper floor forms supported upon shoring built up from this supporting floor. This shoring consists of vertical timbers upon which are laid horizontal stringers, and upon these stringers the panels are placed which form the bottom of the form proper. Now, the bottoms of the several supporting slabs or' abacuses, are of course, below the bottom of the floor, six or eight inches, and the present practice is to erect separate shoring to support the special panels upon which the concrete for these slabs is cast. a v

In accordance with the present invention, I do away with this sel'barate shoring for the slab panels, and support them" from the floor shoring and the floor panels, thus effecting a considerable saving in both lumber and labor. To do this, it has been necessary, first of all to design specially reenforced panels, for without supporting shoring beneath them, these panels must sustain a very heavy load during the pouring and setting of the concrete. At thesame timeI have designed a new floor panel which, because of its'gr'eat-' or strength, is not only superior in its ordinary use, but is better adapted for carrying a part of the strain borne by adjacent slab panels. 2 a y A preferred embodiment of my" invention is illustrated in the accompanying drawings, a study oi which will make clear the principles' involved. In these drawings, Fig; 1 1s a perspective View of a floor form rovided with the speeial slab or abacus forms of the present invention, and showing the general relations'of the various parts of the form; Fig. 2 is aperspective View partly in section of the under or reen'torced side or the improved floorpanel; Fig. 3 is a perspeetive view of one of the supporting Z- bars which support the slab panels; Fig. 4 is a, perspective view ot-one oi the slab panels; Fig. 5 is a perspective view of one of the connecting and stifiening bars which are bolted to the underside of the slab panels during use; Fig. 6 is a plan view of the assembled slab panels; Fig. 7 is a view of the undersides of the panels illustrated in Fig. 6 and showing the connecting bars in place; Fig. 8 is a vertical section through the flooring, slab, and column forms show-' ing the parts in readiness for pouring; and Fig. 9 is a view of the completed floor with its supporting columns and abacuses.

The ordinary shoring used in concrete floor construction comprises upright timbers 1 upon which are laid horizontal stringers 2. .It is sometimes customary to lay upon these horizontal beams a secondsetof timbers ru'nnii'ig at right angles thereto and spaced closer together; W/Vith such a 0611- struction smaller and weaker floor panels can be employed. However, with the reenforced, floor panels of the present invention, it is not necessary to employ these secondary stringers and the panels 3 can be laid directly upon the. first set, as clearly shown in Fig, v I

At intervals provision must be made for the supporting columns. At these points the horizontal stringers 2 are broken asshown at 4 in Fig' 1, and when the floor panels are laid a square opening will be formed at this point. It is through this opening that the column with its abacus form rises to meet the floor. Instead of supporting the abacus or slab panels by separate shoring as is'customary, I proceed as followsz' Around-the edge of the opening in the floor panels, I place a series of Z-bars 5, the npperflanges of which overlap the edges of the adjacent floor panels and aresupported thereby. The lower flanges of these Z-bars, cut away at 6 in order to fit at the corners, support the slab panels and the depth of the webs of these bars determines the thickness of the slabs. Four panels 7 are used for each slab,

one fitting in each corner and each provided with a cut-away quadrant to provide for the column form. These slabs 7 are constructed of sheet metal and reenforced by means of diagonal ribs 8 as shown most clearly in Fig. 7. The outer edges of the panels are also bent to form reenforcing flanges 9. The ribs 8 are in the form of metal channels provided with cores of wood to lend resiliency to the whole. As the panels are assembled, each is bolted to its supporting Z-bars by means of bolts 11. These bolts are not altogether necessary when the structure is finally assembled, but during assembly they are needed to prevent accidental displacement of the heavy panels. When all four of the panels are positioned as shown in Figs. 6, 7 and 8 they are bolted together by means of bars 12 which connect adjacent panels and act to reenforce and stiffen the whole structure. The slab panels and Z-bars form a depression in the general floor level. The column form 13 is then positioned as shown in Fig. 8, the reenforcing put in place, and the form is ready for pouring. The completed concrete structure is shown in Fig. 9 in which 16 indicates the floor, 17 the abacuses or floor supporting slabs, 18 the capitals, and 19 the columns.

The improved floor panel 3 shown in detail in Fig. 2 is made of sheet metal, to the lower face of which are secured reenforcing ribs 14, running both longitudinally and transversely of the panel. These ribs are of channel form similar to ribs 8 of the slab panels and like these other ribs, also contain a core of wood 15 giving lightness and resiliency as well as strength to the structure. It is to be observed that along two sides of the slab forms the Z-bars are supported altogether by the reenforced edges of the adj acent fioor slabs, whereas on the other two sides, the horizontal stringers 2 bear the brunt of the burden. A floor panel of the type described and shown is, therefore, desirable for use in this connection although, of course, it is possible to employ panels of other design.

When using the forms on the present invention in constructing concrete buildings, it is unnecessary to employ special shoring to support the abacus or slab panels. This not only means a saving in lumber but a saving in labor, as it takes much less time to position the forms employed by me than it does to build the necessary shoring. The panels are strong and durable and may be used over and over again.

I claim:

1. A form for casting concrete floor-supporting slabs or abacuses, comprising reenforced panels, Z-bars depending from the adjacent shoring and floor panels and supporting the slab panels.

2. In a form for concrete floors, having floor panels and shoring supporting said panels, the combination of a form for floorsupporting slabs or abacuses, comprising a bottom and flanged side walls, the flanges on the side walls overlying the adjacent floor panels or shoring and wholly supporting the slab form.

3. A form for concrete floors comprising the combination of floor panels spaced to provide for floor-supporting column and abacus forms, shoring supporting the floor panels, reenforced panels for the abacus forms, and Z-bars supporting the reenforced panels depending from and supported by the floor panels and the shoring.

1. A form for concrete floors comprising the combination of reenforccd metallic panels, shoring supporting said panels, forms for floor-supporting slabs or abacuses depending from and supported directly by the floor panels.

5. A panel designed for use in concrete forms comprising sheet metal, and reenforcing ribs on the underside thereof, said ribs comprising a metallic casing and a core of wood.

6 A form for casting floor-supporting slabs or abacuses, comprising reenforced panels shaped to provide for ,the column form, and Z-bars serving to support the i panels and act as sides for the form;

7. A form for use in casting concrete floor-supporting slabs or abacuses, comprising a set of reenforced panels shaped to provide for the column form, Z-bars supporting the panels and acting as sides for the form, and bars bolted to the underside of adjacent panels, connecting them and strengthening the structure.

8. A floor mold comprising a principal plate made of metal, ribs of cushioning material and angle bars fitted to said ribs and secured to one side of the principal plate and to said ribs for holding the latter in place.

9. A floor mold comprising a principal plate made of metal, ribs of cushioning material, angle bars fitted to said ribs and secured to one side of the principal plate and to said ribs for holding them in place, and sills applied to the same side of the plate as the ribs and secured by the edges of the plate being bent over said sills.

10. A floor mold comprising a principal plate having cushioning ribs against one face thereof and a securing plate for each rib passing entirely under the same and having its two sides secured to the principal plate.

11. Apparatus as in the preceding claim wherein additional cushioning ribs are secured at the edges of the plate by angle bars secured to the principal plate.

In testimony whereof I affix my signature.

THORALF JAHNSEN. 

